compute initial winding from projected rays

src/pathops/SkPathOpsCubic.h

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPathOpsCubic_DEFINED
 #define SkPathOpsCubic_DEFINED
 
@@ skipping 39 matching lines @@
 
     static bool IsCubic() { return true; }
 
     const SkDPoint& operator[](int n) const { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; }
     SkDPoint& operator[](int n) { SkASSERT(n >= 0 && n < kPointCount); return fPts[n]; }
 
     void align(int endIndex, int ctrlIndex, SkDPoint* dstPt) const;
     double binarySearch(double min, double max, double axisIntercept, SearchAxis xAxis) const;
     double calcPrecision() const;
     SkDCubicPair chopAt(double t) const;
-    bool clockwise(const SkDCubic& whole, bool* swap) const;
-    static bool Clockwise(const SkPoint* pts, double startT, double endT, bool* swap);
     static void Coefficients(const double* cubic, double* A, double* B, double* C, double* D);
     static bool ComplexBreak(const SkPoint pts[4], SkScalar* t, CubicType* cubicType);
     int convexHull(char order[kPointCount]) const;
 
     void debugInit() {
         sk_bzero(fPts, sizeof(fPts));
     }
 
     void dump() const;  // callable from the debugger when the implementation code is linked in
     void dumpID(int id) const;
     void dumpInner() const;
     SkDVector dxdyAtT(double t) const;
     bool endsAreExtremaInXOrY() const;
     static int FindExtrema(const double src[], double tValue[2]);
     int findInflections(double tValues[2]) const;
 
     static int FindInflections(const SkPoint a[kPointCount], double tValues[2]) {
         SkDCubic cubic;
-        cubic.set(a);
-        return cubic.findInflections(tValues);
+        return cubic.set(a).findInflections(tValues);
     }
 
     int findMaxCurvature(double tValues[]) const;
     bool hullIntersects(const SkDCubic& c2, bool* isLinear) const;
     bool hullIntersects(const SkDConic& c, bool* isLinear) const;
     bool hullIntersects(const SkDQuad& c2, bool* isLinear) const;
     bool hullIntersects(const SkDPoint* pts, int ptCount, bool* isLinear) const;
     bool isLinear(int startIndex, int endIndex) const;
     bool monotonicInX() const;
     bool monotonicInY() const;
@@ skipping 21 matching lines @@
         fPts[1] = pts[1];
         fPts[2] = pts[2];
         fPts[3] = pts[3];
         return *this;
     }
 
     SkDCubic subDivide(double t1, double t2) const;
 
     static SkDCubic SubDivide(const SkPoint a[kPointCount], double t1, double t2) {
         SkDCubic cubic;
-        cubic.set(a);
-        return cubic.subDivide(t1, t2);
+        return cubic.set(a).subDivide(t1, t2);
     }
 
     void subDivide(const SkDPoint& a, const SkDPoint& d, double t1, double t2, SkDPoint p[2]) const;
 
     static void SubDivide(const SkPoint pts[kPointCount], const SkDPoint& a, const SkDPoint& d, double t1,
                           double t2, SkDPoint p[2]) {
         SkDCubic cubic;
-        cubic.set(pts);
-        cubic.subDivide(a, d, t1, t2, p);
+        cubic.set(pts).subDivide(a, d, t1, t2, p);
     }
 
+    double top(const SkDCubic& dCurve, double startT, double endT, SkDPoint*topPt) const;
     SkDQuad toQuad() const;
 
     static const int gPrecisionUnit;
 
     SkDPoint fPts[kPointCount];
 };
 
 /* Given the set [0, 1, 2, 3], and two of the four members, compute an XOR mask
    that computes the other two. Note that:
 
    one ^ two == 3 for (0, 3), (1, 2)
    one ^ two <  3 for (0, 1), (0, 2), (1, 3), (2, 3)
    3 - (one ^ two) is either 0, 1, or 2
    1 >> (3 - (one ^ two)) is either 0 or 1
 thus:
    returned == 2 for (0, 3), (1, 2)
    returned == 3 for (0, 1), (0, 2), (1, 3), (2, 3)
 given that:
    (0, 3) ^ 2 -> (2, 1)  (1, 2) ^ 2 -> (3, 0)
    (0, 1) ^ 3 -> (3, 2)  (0, 2) ^ 3 -> (3, 1)  (1, 3) ^ 3 -> (2, 0)  (2, 3) ^ 3 -> (1, 0)
 */
 inline int other_two(int one, int two) {
     return 1 >> (3 - (one ^ two)) ^ 3;
 }
 
 #endif